/*
 * The contents of this file are subject to the terms of the Common Development and
 * Distribution License (the License). You may not use this file except in compliance with the
 * License.
 *
 * You can obtain a copy of the License at legal/CDDLv1.0.txt. See the License for the
 * specific language governing permission and limitations under the License.
 *
 * When distributing Covered Software, include this CDDL Header Notice in each file and include
 * the License file at legal/CDDLv1.0.txt. If applicable, add the following below the CDDL
 * Header, with the fields enclosed by brackets [] replaced by your own identifying
 * information: "Portions Copyright [year] [name of copyright owner]".
 *
 * Copyright 2008-2009 Sun Microsystems, Inc.
 * Portions copyright 2014-2016 ForgeRock AS.
 */
package org.forgerock.opendj.config;

import java.text.NumberFormat;
import java.util.EnumSet;
import java.util.Set;
import java.util.TreeSet;

import org.forgerock.i18n.LocalizableMessage;
import org.forgerock.i18n.LocalizableMessageBuilder;
import org.forgerock.util.Utils;

/** A property definition visitor which can be used to generate syntax usage information. */
public final class PropertyDefinitionUsageBuilder {

    /** Underlying implementation. */
    private static final class MyPropertyDefinitionVisitor extends
            PropertyDefinitionVisitor<LocalizableMessage, Void> {
        /** Flag indicating whether detailed syntax information will be generated. */
        private final boolean isDetailed;

        /** The formatter to use for numeric values. */
        private final NumberFormat numberFormat;

        /** Private constructor. */
        private MyPropertyDefinitionVisitor(boolean isDetailed) {
            this.isDetailed = isDetailed;

            this.numberFormat = NumberFormat.getNumberInstance();
            this.numberFormat.setGroupingUsed(true);
            this.numberFormat.setMaximumFractionDigits(2);
        }

        @Override
        public <C extends ConfigurationClient, S extends Configuration> LocalizableMessage visitAggregation(
            AggregationPropertyDefinition<C, S> d, Void p) {
            return LocalizableMessage.raw("NAME");
        }

        @Override
        public LocalizableMessage visitAttributeType(AttributeTypePropertyDefinition d, Void p) {
            return LocalizableMessage.raw("OID");
        }

        @Override
        public LocalizableMessage visitACI(ACIPropertyDefinition d, Void p) {
            return LocalizableMessage.raw("ACI");
        }

        @Override
        public LocalizableMessage visitBoolean(BooleanPropertyDefinition d, Void p) {
            if (isDetailed) {
                return LocalizableMessage.raw("false | true");
            } else {
                return LocalizableMessage.raw("BOOLEAN");
            }
        }

        @Override
        public LocalizableMessage visitClass(ClassPropertyDefinition d, Void p) {
            if (isDetailed && !d.getInstanceOfInterface().isEmpty()) {
                return LocalizableMessage.raw("CLASS <= " + d.getInstanceOfInterface().get(0));
            } else {
                return LocalizableMessage.raw("CLASS");
            }
        }

        @Override
        public LocalizableMessage visitDN(DNPropertyDefinition d, Void p) {
            if (isDetailed && d.getBaseDN() != null) {
                return LocalizableMessage.raw("DN <= " + d.getBaseDN());
            } else {
                return LocalizableMessage.raw("DN");
            }
        }

        @Override
        public LocalizableMessage visitDuration(DurationPropertyDefinition d, Void p) {
            LocalizableMessageBuilder builder = new LocalizableMessageBuilder();
            DurationUnit unit = d.getBaseUnit();

            if (isDetailed && d.getLowerLimit() > 0) {
                builder.append(DurationUnit.toString(d.getLowerLimit()));
                builder.append(" <= ");
            }

            builder.append("DURATION (");
            builder.append(unit.getShortName());
            builder.append(")");

            if (isDetailed) {
                if (d.getUpperLimit() != null) {
                    builder.append(" <= ");
                    builder.append(DurationUnit.toString(d.getUpperLimit()));
                }

                if (d.isAllowUnlimited()) {
                    builder.append(" | unlimited");
                }
            }

            return builder.toMessage();
        }

        @Override
        public <E extends Enum<E>> LocalizableMessage visitEnum(EnumPropertyDefinition<E> d, Void p) {
            if (!isDetailed) {
                // Use the last word in the property name.
                String name = d.getName();
                int i = name.lastIndexOf('-');
                if (i == -1 || i == (name.length() - 1)) {
                    return LocalizableMessage.raw(name.toUpperCase());
                } else {
                    return LocalizableMessage.raw(name.substring(i + 1).toUpperCase());
                }
            } else {
                Set<String> values = new TreeSet<>();
                for (Object value : EnumSet.allOf(d.getEnumClass())) {
                    values.add(value.toString().trim().toLowerCase());
                }
                return LocalizableMessage.raw(Utils.joinAsString(" | ", values));
            }
        }

        @Override
        public LocalizableMessage visitInteger(IntegerPropertyDefinition d, Void p) {
            LocalizableMessageBuilder builder = new LocalizableMessageBuilder();

            if (isDetailed) {
                builder.append(String.valueOf(d.getLowerLimit()));
                builder.append(" <= ");
            }

            builder.append("INTEGER");

            if (isDetailed) {
                if (d.getUpperLimit() != null) {
                    builder.append(" <= ");
                    builder.append(String.valueOf(d.getUpperLimit()));
                } else if (d.isAllowUnlimited()) {
                    builder.append(" | unlimited");
                }
            }

            return builder.toMessage();
        }

        @Override
        public LocalizableMessage visitIPAddress(IPAddressPropertyDefinition d, Void p) {
            return LocalizableMessage.raw("HOST_NAME");
        }

        @Override
        public LocalizableMessage visitIPAddressMask(IPAddressMaskPropertyDefinition d, Void p) {
            return LocalizableMessage.raw("IP_ADDRESS_MASK");
        }

        @Override
        public LocalizableMessage visitSize(SizePropertyDefinition d, Void p) {
            LocalizableMessageBuilder builder = new LocalizableMessageBuilder();

            if (isDetailed && d.getLowerLimit() > 0) {
                SizeUnit unit = SizeUnit.getBestFitUnitExact(d.getLowerLimit());
                builder.append(numberFormat.format(unit.fromBytes(d.getLowerLimit())));
                builder.append(' ');
                builder.append(unit.getShortName());
                builder.append(" <= ");
            }

            builder.append("SIZE");

            if (isDetailed) {
                if (d.getUpperLimit() != null) {
                    long upperLimit = d.getUpperLimit();
                    SizeUnit unit = SizeUnit.getBestFitUnitExact(upperLimit);

                    // Quite often an upper limit is some power of 2 minus 1. In
                    // those
                    // cases lets use a "less than" relation rather than a "less
                    // than
                    // or equal to" relation. This will result in a much more
                    // readable
                    // quantity.
                    if (unit == SizeUnit.BYTES && upperLimit < Long.MAX_VALUE) {
                        unit = SizeUnit.getBestFitUnitExact(upperLimit + 1);
                        if (unit != SizeUnit.BYTES) {
                            upperLimit += 1;
                            builder.append(" < ");
                        } else {
                            builder.append(" <= ");
                        }
                    } else {
                        builder.append(" <= ");
                    }

                    builder.append(numberFormat.format(unit.fromBytes(upperLimit)));
                    builder.append(' ');
                    builder.append(unit.getShortName());
                }

                if (d.isAllowUnlimited()) {
                    builder.append(" | unlimited");
                }
            }

            return builder.toMessage();
        }

        @Override
        public LocalizableMessage visitString(StringPropertyDefinition d, Void p) {
            if (d.getPattern() != null) {
                if (isDetailed) {
                    LocalizableMessageBuilder builder = new LocalizableMessageBuilder();
                    builder.append(d.getPatternUsage());
                    builder.append(" - ");
                    builder.append(d.getPatternSynopsis());
                    return builder.toMessage();
                } else {
                    return LocalizableMessage.raw(d.getPatternUsage());
                }
            } else {
                return LocalizableMessage.raw("STRING");
            }
        }

        @Override
        public <T> LocalizableMessage visitUnknown(PropertyDefinition<T> d, Void p) {
            return LocalizableMessage.raw("?");
        }
    }

    /** Underlying implementation. */
    private final MyPropertyDefinitionVisitor pimpl;

    /**
     * Creates a new property usage builder.
     *
     * @param isDetailed
     *            Indicates whether the generated usage should contain
     *            detailed information such as constraints.
     */
    public PropertyDefinitionUsageBuilder(boolean isDetailed) {
        this.pimpl = new MyPropertyDefinitionVisitor(isDetailed);
    }

    /**
     * Generates the usage information for the provided property definition.
     *
     * @param pd
     *            The property definitions.
     * @return Returns the usage information for the provided property
     *         definition.
     */
    public LocalizableMessage getUsage(PropertyDefinition<?> pd) {
        return pd.accept(pimpl, null);
    }
}
